Lactobacillus rhamnosus cncm i-4096 and weight control

ABSTRACT

The present invention generally relates to the field of obesity. In particular the present invention relates to the use of probiotics to support weight management and to treat or prevent obesity. One embodiment of the present invention relates to the use of  Lactobacillus rhamnosus  CNCM I-4096 for the preparation of a composition to support weight management, promote weight loss and/or to treat obesity.

The present invention generally relates to the field of weightmanagement. In particular the present invention relates to the use ofprobiotics to support weight management, promote weight loss and/or totreat obesity.

During the past decades, the prevalence of obesity has increasedworldwide to epidemic proportion. Approximately 1 billion of peopleworldwide are overweight or obese, conditions that increase mortality,mobility and economical costs. Obesity develops when energy intake isgreater than energy expenditure, the excess energy being stored mainlyas fat in adipose tissue. Body weight loss and prevention of weight gaincan be achieved by reducing energy intake or bioavailability, increasingenergy expenditure and/or reducing storage as fat. Obesity represents aserious threat to health because it is associated with an array ofchronic diseases, including diabetes, atherosclerosis, degenerativedisorders, airway diseases and some cancers.

Modifications of the intestinal flora were recently associated withobesity. These changes were demonstrated in obese mice to affect themetabolic potential of gut microbiota resulting in an increased capacityto harvest energy from the diet (Turnbaugh P J, Ley R E, Mahowald M A,Magrini V, Mardis E R, Gordon J I. An obesity-associated gut microbiomewith increased capacity for energy harvest. Nature. 2006; Ley R E,Turnbaugh P J, Klein S, Gordon J I. Microbial ecology: human gutmicrobes associated with obesity. Nature. 2006). Such modifications ofgut microbiota are proposed to contribute to the pathophysiology ofobesity. Probiotics, the beneficial bacteria present in food or foodsupplements, are known to modify the intestinal microbiota (Fuller R &Gibson G R. Modification of the intestinal microflora using probioticsand prebiotics. Scand J. Gastroenterol. 1997).

WO2006019222 discloses the Lactobacillus rhamnosus Strain PL60KCCM-10654P with a body-fat reducing activity that overproducest10c12-octadecadienoic acid.

However the overproduction of t10c12-octadecadienoic acid might beproblematic for patients that react sensitively ont10c12-octadecadienoic acid.

US7001756 and CN1670183 provide an isolated microorganism strain,Lactobacillus rhamnosus GM-020, which is found to be effective intreating obesity.

Based on this prior art it was the object of the present invention toidentify alternative probiotic bacteria that do not rely on theoverexpression of t10c12-octadecadienoic acid and/or that offer anattractive effectiveness that can be used to treat obesity and thatovercomes disadvantages of the strains of the prior art.

This object is achieved by the use of claim 1.

The present inventors have found that—unexpectedly—the strainLactobacillus rhamnosus NCC 2907 achieves this object.

Lactobacillus rhamnosus NCC 2907 was deposited under the Budapest treatywith the Collection Nationale de Cultures de Microorganism, InstitutPasteur, 25, Rue du Docteur Roux, F-76724 Paris Cedex 15 as CNCM I-4096.

Hence, one embodiment of the present invention is the use ofLactobacillus rhamnosus CNCM I-4096 for the preparation of a compositionto treat obesity in animals.

A further embodiment of the present invention is the use ofLactobacillus rhamnosus CNCM I-4096 for the preparation of a compositionto promote weight loss.

Still, a further embodiment of the present invention is the use ofLactobacillus rhamnosus CNCM I-4096 for the preparation of a compositionto support weight management.

The compositions described in the framework of the present invention arein particular beneficial for long term applications. The inventors haveshown in an animal model that a mouse treated with the compositiondescribed in the present invention will put on significantly less weightthan a control mouse if fed a high caloric diet. This effect was themore pronounced the longer the composition was administered. Theexperiment was continued for about two months and the observed effectsincreased with time.

Consequently, in a preferred embodiment of the present invention, thecomposition is to be administered for at least 2 weeks, at least 3weeks, at least 4 weeks, at least 5 weeks, at least 6 weeks, at least 7weeks, and/or at least 8 weeks.

In this specification, the following terms have the following meanings:

“Animal” means animals including humans.

The term “Lactobacillus rhamnosus CNCM I-4096” is meant to include thebacterium, a cell growth medium with the bacterium or a cell growthmedium in which Lactobacillus rhamnosus CNCM I-4096 was cultivated.Lactobacillus rhamnosus CNCM I-4096 may be present as viable bacteria,as non-replicating bacteria, or as a mixture thereof.

“Body mass index” or “BMI” means the ratio of weight in Kg divided bythe height in metres, squared.

“Overweight” is defined for an adult human as having a BMI between 25and 30.

“Obesity” is a condition in which the natural energy reserve, stored inthe fatty tissue of animals, in particular humans and other mammals, isincreased to a point where it is associated with certain healthconditions or increased mortality. “Obese” is defined for an adult humanas having a BMI greater than 30.

“Probiotic” means microbial cell preparations or components of microbialcells with a beneficial effect on the health or well-being of the host.(Salminen S, Ouwehand A. Benno Y. et al “Probiotics: how should they bedefined” Trends Food Sci. Technol. 1999:10 107-10).

“Prebiotic” means food substances intended to promote the growth ofprobiotic bacteria in the intestines.

“Food grade bacteria” means bacteria that are used and generallyregarded as safe for use in food.

“Weight loss” in the context of the present invention is a reduction ofthe total body weight. Weight loss may for example refer to the loss oftotal body mass in an effort to improve fitness, health, and/orappearance.

“Weight management” or “weight maintenance” relates to maintaining atotal body weight. For example, weight management may relate tomaintaining a BMI in the area of 18.5-25 which is considered to benormal.

The composition of the present invention may further contain protectivehydrocolloids (such as gums, proteins, modified starches), binders, filmforming agents, encapsulating agents/materials, wall/shell materials,matrix compounds, coatings, emulsifiers, surface active agents,solubilising agents (oils, fats, waxes, lecithins etc.), adsorbents,carriers, fillers, co-compounds, dispersing agents, wetting agents,processing aids (solvents), flowing agents, taste masking agents,weighting agents, jellifying agents, gel forming agents, antioxidantsand antimicrobials. The composition may also contain conventionalpharmaceutical additives and adjuvants, excipients and diluents,including, but not limited to, water, gelatine of any origin, vegetablegums, ligninsulfonate, talc, sugars, starch, gum arabic, vegetable oils,polyalkylene glycols, flavouring agents, preservatives, stabilizers,emulsifying agents, buffers, lubricants, colorants, wetting agents,fillers, and the like. In all cases, such further components will beselected having regard to their suitability for the intended recipient.

The composition may be a nutritionally complete formula.

The composition according to the invention may comprise a source ofprotein.

Any suitable dietary protein may be used, for example animal proteins(such as milk proteins, meat proteins and egg proteins); vegetableproteins (such as soy protein, wheat protein, rice protein, and peaprotein); mixtures of free amino acids; or combinations thereof. Milkproteins such as casein and whey, and soy proteins are particularlypreferred.

The proteins may be intact or hydrolysed or a mixture of intact andhydrolysed proteins. It may be desirable to supply partially hydrolysedproteins (degree of hydrolysis between 2 and 20%), for example foranimals believed to be at risk of developing cows' milk allergy. Ifhydrolysed proteins are required, the hydrolysis process may be carriedout as desired and as is known in the art. For example, a whey proteinhydrolysate may be prepared by enzymatically hydrolysing the wheyfraction in one or more steps. If the whey fraction used as the startingmaterial is substantially lactose free, it is found that the proteinsuffers much less lysine blockage during the hydrolysis process. Thisenables the extent of lysine blockage to be reduced from about 15% byweight of total lysine to less than about 10% by weight of lysine; forexample about 7% by weight of lysine which greatly improves thenutritional quality of the protein source.

The composition may also contain a source of carbohydrates and a sourceof fat.

If the composition includes a fat source, the fat source preferablyprovides 5% to 40% of the energy of the composition; for example 20% to30% of the energy. A suitable fat profile may be obtained using a blendof canola oil, corn oil and high-oleic acid sunflower oil.

A source of carbohydrates may be added to the composition.

The source of carbohydrates preferably provides about 40% to 80% of theenergy of the composition. Any suitable carbohydrate may be used, forexample sucrose, lactose, glucose, fructose, corn syrup solids,maltodextrins, and mixtures thereof. Dietary fibre may also be added ifdesired. Dietary fibre passes through the small intestine undigested byenzymes and functions as a natural bulking agent and laxative. Dietaryfibre may be soluble or insoluble and in general a blend of the twotypes is preferred. Suitable sources of dietary fibre include soy, pea,oat, pectin, guar gum, gum Arabic, fructooligosaccharides,galacto-oligosaccharides, sialyl-lactose and oligosaccharides derivedfrom animal milks. A preferred fibre blend is a mixture of inulin withshorter chain fructo-oligosaccharides. Preferably, if fibre is present,the fibre content is between 2 and 40 g/l of the composition asconsumed, more preferably between 4 and 10 g/l.

The composition may also contain minerals and micronutrients such astrace elements and vitamins in accordance with the recommendations ofGovernment bodies such as the USRDA

One or more food grade emulsifiers may be incorporated into thecomposition if desired; for example diacetyl tartaric acid esters ofmono- and di-glycerides, lecithin and mono- and di-glycerides. Similarlysuitable salts and stabilisers may be included.

The composition is preferably orally or enterally administrable; forexample in the form of a powder for re-constitution with milk or water.

Preferably, the composition is provided in the form of a powder, e.g., ashelf stable powder. Shelf stability can be obtained, for example byproviding the composition with a water activity smaller than 0.2, forexample in the range of 0.19-0.05, preferably smaller than 0.15.

Water activity or a_(w) is a measurement of the energy status of thewater in a system. It is defined as the vapour pressure of water dividedby that of pure water at the same temperature; therefore, pure distilledwater has a water activity of exactly one.

The composition described above may be prepared in any suitable manner.For example, it may be prepared by blending together the protein, thecarbohydrate source, and the fat source in appropriate proportions. Ifused, the emulsifiers may be included at this point. The vitamins andminerals may be added at this point but are usually added later to avoidthermal degradation. Any lipophilic vitamins, emulsifiers and the likemay be dissolved into the fat source prior to blending. Water,preferably water which has been subjected to reverse osmosis, may thenbe mixed in to form a liquid mixture. The temperature of the water isconveniently about 50° C. to about 80° C. to aid dispersal of theingredients. Commercially available liquefiers may be used to form theliquid mixture. The liquid mixture is then homogenised; for example intwo stages.

The liquid mixture may then be thermally treated to reduce bacterialloads, by rapidly heating the liquid mixture to a temperature in therange of about 80° C. to about 150° C. for about 5 seconds to about 5minutes, for example. This may be carried out by steam injection,autoclave or by heat exchanger; for example a plate heat exchanger.

Then, the liquid mixture may be cooled to about 60° C. to about 85° C.;for example by flash cooling. The liquid mixture may then be againhomogenised; for example in two stages at about 10 MPa to about 30 MPain the first stage and about 2 MPa to about 10 MPa in the second stage.The homogenised mixture may then be further cooled to add any heatsensitive components; such as vitamins and minerals. The pH and solidscontent of the homogenised mixture are conveniently adjusted at thispoint.

The homogenised mixture is transferred to a suitable drying apparatussuch as a spray drier or freeze drier and converted to powder. Thepowder should have a moisture content of less than about 5% by weight.

Lactobacillus rhamnosus CNCM I-4096 may be cultured according to anysuitable method and prepared for addition to the composition byfreeze-drying or spray-drying for example. Appropriate culturing methodsfor Lactobacillus rhamnosus CNCM I-4096 are known to those skilled inthe art. Alternatively, bacterial preparations can be bought fromspecialist suppliers such as Christian Hansen and Danisco alreadyprepared in a suitable form for addition to food products such asnutritional and infant formulas. The probiotic bacteria may be added tothe formula in an appropriate amount, preferably between 10² and 10¹²cfu/g powder, more preferably between 10⁷ and 10¹² cfu/g powder.

In one embodiment of the present invention the animals to be treatedwith the composition prepared by the use of the present invention are atleast two years old. This age limit applies in particular to humans. Ifthe animals to be treated with the composition prepared by the use ofthe present invention are dogs or cats, for example, the dog or catshould be at least 4 months old.

In one embodiment of the present invention the composition is amedicament. As a medicament the dosage of Lactobacillus rhamnosus CNCMI-4096 can be carefully adjusted according to a doctor's recommendation.

The composition prepared according to the present may also be a foodproduct. As a food product the beneficial effects of Lactobacillusrhamnosus CNCM I-4096 would be available to everyone. Lactobacillusrhamnosus CNCM I-4096 could thus be easily used by everybody to supportweight management. Treatment or prevention of obesity could be initiatedat a much earlier stage. Further, in a food product Lactobacillusrhamnosus CNCM I-4096 would be even more pleasant to consume. Examplesof food products that are applicable to the present invention areyoghurts, milk, flavoured milk, ice cream, ready to east desserts,powders for re-constitution with, e.g., milk or water, chocolate milkdrinks, malt drinks, ready-to-eat dishes, instant dishes or drinks forhumans or food compositions representing a complete or a partial dietintended for pets or livestock.

Consequently, in one embodiment the composition according to the presentinvention is a food product intended for humans, pets or livestock. Inparticular the composition is intended for animals selected from thegroup consisting of dogs, cats, pigs, cattle, horses, goats, sheep,poultry. In a preferred embodiment is the composition a food productintended for adult species, in particular human adults.

The composition of the present invention may also comprise at least oneother kind of other food grade bacteria or yeast. The food gradebacteria may be probiotic bacteria and are preferably selected from thegroup consisting of lactic acid bacteria, bifidobacteria,propionibacteria or mixtures thereof. Probiotic bacteria may be anylactic acid bacteria or Bifidobacteria with established probioticcharacteristics. For example they may be also capable of promoting thedevelopment of a bifidogenic intestinal microbiota. Suitable probioticBifidobacteria strains include Bifidobacterium lactis CNCM I-3446 soldinter alia by the Christian Hansen company of Denmark under the trademark Bb12, Bifidobacterium longum ATCC BAA-999 sold by Morinaga MilkIndustry Co. Ltd. of Japan under the trade mark BB536, the strain ofBifidobacterium breve sold by Danisco under the trade mark Bb-03, thestrain of Bifidobacterium breve sold by Morinaga under the trade markM-16V and the strain of Bifidobacterium breve sold by Institut Rosell(Lallemand) under the trade mark R0070. A mixture of suitable probioticlactic acid bacteria and Bifidobacteria may be used.

As food grade yeast the following can be used for example Saccharomycescerevisiae and/or Saccharomyces boulardii.

In a preferred embodiment of the present invention the compositionfurther contains at least one prebiotic. Prebiotics can promote thegrowth of certain food grade bacteria, in particular of probioticbacteria, in the intestines and can hence enhance the effect ofLactobacillus rhamnosus CNCM I-4096. Furthermore, several prebioticshave a positive influence on, e.g., digestion.

Preferably the prebiotic is selected from the group consisting ofoligosaccharides and optionally contain fructose, galactose, mannose,soy and/or inulin; dietary fibers; or mixtures thereof.

The compositions may contain at least one prebiotic in an amount of 0.3to 10% dry weight of the composition. Prebiotics are non-digestible foodingredients that beneficially affect the host by selectively stimulatingthe growth and/or activity of one or a limited number of bacteria in thecolon, and thus improve host health. Such ingredients are non-digestiblein the sense that they are not broken down and absorbed in the stomachor small intestine and thus pass intact to the colon where they areselectively fermented by the beneficial bacteria.

Further examples of prebiotics include certain oligosaccharides, such asfructooligosaccharides (FOS) and galactooligosaccharides (GOS). Acombination of prebiotics may be used, such as 90% GOS with 10% shortchain fructo-oligosaccharides such as the product sold under the trademark Raftilose® or 10% inulin such as the product sold under the trademark Raftiline®.

A particularly preferred prebiotic is a mixture ofgalacto-oligosaccharide(s), N-acetylated oligosaccharide(s) andsialylated oligosaccharide(s) in which the N-acetylatedoligosaccharide(s) comprise 0.5 to 4.0% of the oligosaccharide mixture,the galacto-oligosaccharide(s) comprise 92.0 to 98.5% of theoligosaccharide mixture and the sialylated oligosaccharide(s) comprise1.0 to 4.0% of the oligosaccharide mixture. This mixture is hereinafterreferred to as “CMOS-GOS”. Preferably, a composition for use accordingto the invention contains from 2.5 to 15.0 wt % CMOS-GOS on a dry matterbasis with the proviso that the composition comprises at least 0.02 wt %of an N-acetylated oligosaccharide, at least 2.0 wt % of agalacto-oligosaccharide and at least 0.04 wt % of a sialylatedoligosaccharide.

Suitable N-acetylated oligosaccharides include GalNAcα1,3Galβ1,4Glc andGalβ1,6GalNAcα1,3Galβ1,4Glc. The N-acetylated oligosaccharides may beprepared by the action of glucosaminidase and/or galactosaminidase onN-acetyl-glucose and/or N-acetyl galactose. Equally, N-acetyl-galactosyltransferases and/or N-acetyl-glycosyl transferases may be used for thispurpose. The N-acetylated oligosaccharides may also be produced byfermentation technology using respective enzymes (recombinant ornatural) and/or microbial fermentation. In the latter case the microbesmay either express their natural enzymes and substrates or may beengineered to produce respective substrates and enzymes. Singlemicrobial cultures or mixed cultures may be used. N-acetylatedoligosaccharide formation can be initiated by acceptor substratesstarting from any degree of polymerisation (DP) from DP=1 onwards.Another option is the chemical conversion of keto-hexoses (e.g.fructose) either free or bound to an oligosaccharide (e.g. lactulose)into N-acetylhexosamine or an N-acetylhexosamine containingoligosaccharide as described in Wrodnigg, T. M.; Stutz, A. E. (1999)Angew. Chem. Int. Ed. 38:827-828.

Suitable galacto-oligosaccharides include Galβ1,6Gal, Galβ1,6Galβ1,4GlcGalβ1,6Galβ1,6Glc, Galβ1,3Galβ1,3Glc, Galβ1,3Galβ1,4Glc,Galβ1,6Galβ1,6Galβ1,4Glc, Galβ1,6Galβ1,3Galβ1,4GlcGalβ1,3Galβ1,6Galβ1,4Glc, Galβ1,3Galβ1,3Galβ1,4Glc, Galβ1,4Galβ1,4Glcand Galβ1,4Galβ1,4Galβ1,4Glc. Synthesised galacto-oligosaccharides suchas Galβ1,6Galβ1,4Glc Galβ1,6Galβ1,6Glc, Galβ1,3Galβ1,4Glc,Galβ1,6Galβ1,6Galβ1,4Glc, Galβ1,6Galβ1,3Galβ1,4Glc andGalβ1,3Galβ1,6Galβ1,4Glc, Galβ1,4Galβ1,4Glc and Galβ1,4Galβ1,4Galβ1,4Glcand mixtures thereof are commercially available under the trade marksVivinal® and Elix'or®. Other suppliers of oligosaccharides are DextraLaboratories, Sigma-Aldrich Chemie GmbH and Kyowa Hakko Kogyo Co., Ltd.Alternatively, specific glycoslytransferases, such asgalactosyltransferases may be used to produce neutral oligosaccharides.

Suitable sialylated oligosaccharides include NeuAcα2,3Galβ1,4Glc andNeuAcα2,6Galβ1,4Glc. These sialylated oligosaccharides may be isolatedby chromatographic or filtration technology from a natural source suchas animal milks. Alternatively, they may also be produced bybiotechnology using specific sialyltransferases either by enzyme basedfermentation technology (recombinant or natural enzymes) or by microbialfermentation technology. In the latter case microbes may either expresstheir natural enzymes and substrates or may be engineered to producerespective substrates and enzymes. Single microbial cultures or mixedcultures may be used. Sialyl-oligosaccharide formation can be initiatedby acceptor substrates starting from any degree of polymerisation (DP)from DP=1 onwards.

One advantage of the present invention is that Lactobacillus rhamnosusCNCM I-4096 are effective, both, as living bacterium as well asinactivated bacterial species. Consequently, even conditions that willnot allow the presence of living bacteria will not abolish theeffectiveness of Lactobacillus rhamnosus CNCM I-4096.

It is preferred, however that at least a part of the Lactobacillusrhamnosus CNCM I-4096 are alive in the composition and preferably arrivealive in the intestine. This way they can colonize the intestine andincrease their effectiveness by multiplication.

However, for special sterile food products or medicaments it might bepreferable that Lactobacillus rhamnosus CNCM I-4096 are not alive in thecomposition. Hence, in one embodiment of the present invention at leasta part of the Lactobacillus rhamnosus CNCM I-4096 are not alive in thecomposition.

Lactobacillus rhamnosus CNCM I-4096 will be effective in anyconcentration. If Lactobacillus rhamnosus CNCM I-4096 reaches theintestine alive, a single bacterium can theoretically be sufficient toachieve a powerful effect by colonization and multiplication.

However, for a medicament it is generally preferred that a daily dose ofthe medicament comprises between 10² and 10¹² cfu of Lactobacillusrhamnosus CNCM I-4096. A particular suitable daily dose of Lactobacillusrhamnosus CNCM I-4096 is from 10⁵ to 10¹¹ colony forming units (cfu),more preferably from 10⁷ to 10¹⁰ cfu.

In the case of inactivated Lactobacillus rhamnosus CNCM I-4096 it isgenerally preferred that a daily dose of the medicament comprisesbetween 10² and 10¹² cells of Lactobacillus rhamnosus CNCM I-4096. Aparticular suitable daily dose of Lactobacillus rhamnosus CNCM I-4096 isfrom 10⁵ to 10¹¹ cells, more preferably from 10⁷ to 10¹⁰ cells.

For a food composition it is generally preferred that it comprisesbetween 10³ and 10¹² cfu of Lactobacillus rhamnosus CNCM I-4096 per g ofthe dry weight of the food composition. A particular suitable amount ofLactobacillus rhamnosus CNCM I-4096 is from 10⁵ to 10¹¹ cfu per g of thedry weight of the food composition, more preferably from 10⁷ to 10¹⁰ cfuper g of the dry weight of the food composition.

In the case of inactivated Lactobacillus rhamnosus CNCM I-4096 it isgenerally preferred that the food composition comprises between 10³ and10¹² cells of Lactobacillus rhamnosus CNCM I-4096 per g of the dryweight of the food composition. A particular suitable amount ofLactobacillus rhamnosus CNCM I-4096 is from 10⁵ to 10¹¹ cells per g ofthe dry weight of the food composition, more preferably from 10⁷ to 10¹⁰cells per g of the dry weight of the food composition.

The daily dose of Lactobacillus rhamnosus CNCM I-4096 in a compositionwill depend on the particular person or animal to be treated. Importantfactors to be considered include age, body weight, sex and healthcondition.

For example a typical daily dose of Lactobacillus rhamnosus CNCM I-4096in a composition will be in the range of 10⁴-10¹² cfu and/or cells perday, preferably 10⁶-10¹⁰ cfu and/or cells per day, preferably 10⁷-10⁹cfu and/or cells per day.

A further use of a composition comprising Lactobacillus rhamnosus CNCMI-4096 according to the present invention is to support weight lossand/or weight maintenance.

Since establishing and maintaining a proper body weight and—inparticular—an acceptable weight percentage of fat in the body is a keystep to treat or prevent metabolic disorders, a further use of acomposition comprising Lactobacillus rhamnosus CNCM I-4096 according tothe present invention is to treat or prevent metabolic disorders.

In particular, a composition comprising Lactobacillus rhamnosus CNCMI-4096 according to the present invention can be used to treat orprevent diabetes, hypertension and/or cardiovascular diseases and canhence make a significant contribution to the well-being of today'spopulation in a number countries, in particular, in well developedcountries.

The present invention also relates to a composition comprisingLactobacillus rhamnosus CNCM I-4096 for use in the treatment and/orprevention of the conditions described herein.

It is clear to those skilled in the art that any features described inthis specification can be combined freely without departing from thescope of the present invention as disclosed.

Further features and advantages of the present invention result from thefollowing Examples and Figures:

FIG. 1 shows the weight gain in the ob/ob mice treated or not with L.rhamnosus NCC2907. It is clear that long term administration (50 days)of the Lactobacillus rhamnosus NCC2907 at 10⁹-10¹⁰ CFU per day preventsweight gain in hyperphagic obese mice (ob/ob).

FIG. 2 shows the fat mass gain in ob/ob mice treated or not with L.rhamnosus NCC2907. It is clear that the observed reduction of weightgain of FIG. 1 is associated with a reduction of fat mass gain.

EXAMPLE

Seven to eight weeks-old male obese ob/ob mice were fed a chow diet andtreated with 10⁹-10¹⁰ cfu Lactobacillus rhamnosus NCC2907 per day for 50days. Lactobacillus rhamnosus NCC2907 biomass diluted in the MRS mediumwas administrated in the drinking solution containing NaCl 9/1000, thecontrol group received the saline solution with corresponding amount ofMRS medium present in the probiotic preparation. Body weight wasfollowed during the study and body composition, assessed by NMR, wasmeasured before and at the end of the treatment.

Body weight gain of both obese (ob/ob) mice receiving Lactobacillusrhamnosus NCC2907 in the drinking solution was reduced by about 25%after 50 days, as compared with the control group (FIG. 1).

Administration of the Lactobacillus rhamnosus NCC2907 strain induced areduction of fat mass gain in obese mice as compared to control animals(FIG. 2).

1. A method for weight loss in a mammal comprising the step ofadministering a composition comprising Lactobacillus rhamnosus CNCMI-4096 to a mammal in need of weight loss.
 2. Method in accordance withclaim 1, wherein the mammal is a human at least 2 years old.
 3. Methodin accordance with claim 1 wherein the composition is selected from thegroup consisting of a medicament and a food product.
 4. Method inaccordance with claim 1, wherein the composition comprises at least oneother kind of other food grade bacteria and/or yeast.
 5. Method inaccordance with claim 4, wherein the food grade bacteria is selectedfrom the group consisting of lactic acid bacteria, bifidobacteria,propionibacteria and mixtures thereof.
 6. Method in accordance withclaim 1 wherein the composition contains at least one prebiotic. 7.Method in accordance with claim 6 wherein the prebiotic is selected fromthe group consisting of oligosaccharides; inulin; dietary fibers; andmixtures thereof.
 8. Method in accordance with claim 1 wherein at leasta part of the Lactobacillus rhamnosus CNCM I-4096 are alive in thecomposition.
 9. Method in accordance with claim 1 wherein at least apart of the Lactobacillus rhamnosus CNCM I-4096 are not alive in thecomposition.
 10. Method in accordance with claim 1 wherein thecomposition is a medicament that comprises between 10² and 10¹² cfu ofLactobacillus rhamnosus CNCM I-4096 per daily dose.
 11. Method inaccordance with claim 1 wherein the composition is a food product thatcomprises between 10³ and 10¹² cfu of Lactobacillus rhamnosus CNCMI-4096 per g of the dry weight of the food composition.
 12. Method inaccordance with claim 1 to treat obesity.
 13. Method in accordance withclaim 1 to reduce fat mass gain.
 14. Method in accordance with claim 1to treat metabolic disorders.
 15. Lactobacillus rhamnosus CNCM I-4096.16. A method for weight maintenance in a mammal comprising the step ofadministering a composition comprising Lactobacillus rhamnosus CNCMI-4096 to a mammal in need of weight loss.
 17. Method in accordance withclaim 16, wherein the mammal is a human at least 2 years old.
 18. Methodin accordance with claim 16 wherein the composition is selected from thegroup consisting of a medicament and a food product.
 19. Method inaccordance with claim 16, wherein the composition comprises at least oneother kind of other food grade bacteria and/or yeast.
 20. Method inaccordance with claim 19, wherein the food grade bacteria is selectedfrom the group consisting of lactic acid bacteria, bifidobacteria,propionibacteria and mixtures thereof.
 21. Method in accordance withclaim 16 wherein the composition contains at least one prebiotic. 22.Method in accordance with claim 21 wherein the prebiotic is selectedfrom the group consisting of oligosaccharides; inulin; dietary fibers;and mixtures thereof.
 23. Method in accordance with claim 16 wherein atleast a part of the Lactobacillus rhamnosus CNCM I-4096 are alive in thecomposition.
 24. Method in accordance with claim 16 wherein at least apart of the Lactobacillus rhamnosus CNCM I-4096 are not alive in thecomposition.
 25. Method in accordance with claim 16 wherein thecomposition is a medicament that comprises between 10² and 10¹² cfu ofLactobacillus rhamnosus CNCM I-4096 per daily dose.
 26. Method inaccordance with claim 16 wherein the composition is a food product thatcomprises between 10³ and 10¹² cfu of Lactobacillus rhamnosus CNCMI-4096 per g of the dry weight of the food composition.
 27. Method inaccordance with claim 16 to reduce fat mass gain.
 28. Method inaccordance with claim 16 to treat metabolic disorders.
 29. Method inaccordance with claim 1 wherein the composition is a medicament thatcomprises between 10² and 10¹² cells of Lactobacillus rhamnosus CNCMI-4096 per daily dose.
 30. Method in accordance with claim 16 whereinthe composition is a medicament that comprises between 10² and 10¹²cells of Lactobacillus rhamnosus CNCM I-4096 per daily dose.
 31. Methodin accordance with claim 1 wherein the composition is a food productthat comprises between 10³ and 10¹² cells of Lactobacillus rhamnosusCNCM I-4096 per g of the dry weight of the food composition.
 32. Methodin accordance with claim 16 wherein the composition is a food productthat comprises between 10³ and 10¹² cells of Lactobacillus rhamnosusCNCM I-4096 per g of the dry weight of the food composition.